Insulator.



iL'sAYER.

msumox. APPLICATION FILED MAY 26. 1916.

PantedMar. 6, 1917.

4 d f A ml WITN ESSES INVENTOFI ATTORNEY NTD STATES JOHN SAYER, OF FLAG-STAFF, ARIZONA.

INSULATOB.

Application led May 26, 1916.

To aZZ whom/15 may concer-n.'

Be it known that l, donn Sarra, a subject of the King of Great Britain, residing at Flagstaff, in the county of Coconino and Sta-te of Arizona, havev ii vented certain new and useful mprovements in nsulators, of which the following is a specification.

This invention relates to insulators, and has particular reference to improvements in means for strengthening or reinforcing various forms of fragile insulators.

The primary object of the invention is to provide an insulator constructed of porcelain or other similar fragile plastic having embedded therein a reinforcing element or core, whereby the insulator is rendered less liable of becoming broken, and wherel'iy the effectiveness of the insulator is in no way impaired.

A further object ofthe invention is to provide insulators of this character and for this purpose which may be easily constructed at but small expense, which are composed of but few extremely simple and inexpensive parts, and which will prove thoroughly efficient in the attainment of the ends for which they are designed.

Vith these objects in view, together with others which will appear as the description proceeds, the invention resides in the novel formation, combination and arrangement of parts, all as will be described more fully hereinafter, illustrated in the drawings, and particularly pointed out in, the claims.

The invention will be best understood by reference to the accompanying drawings, wherein:

Figure 1 is a longitudinal sectional view taken through an insulator' constructed in accordance with the invention,

Fig. 2 is an enlarged transverse sectional view taken through the device illustrated in Fig. 1,

Fig. 3 is a fragmentary longitudinal sectional view taken through an insulator embodying a slightly modified form of the invention,

Fig. t is a transverse sectional view taken on line 4 4 of Fig. 8,

Fig. 5 is a view similar to Fig. 3 and illustrating a still further modified form of the invention, and

Fig. 6 is a transverse sectional view taken on line 6 6 of Fig. 5.

In the present instance, the invention is Specification of Letters Patent.

Patented Mar. G, 1917.

seran no. 100,144..

illustrated as used in connection with la common form of spark plug for use with internal combustion engines, but it is to be understood that the invention is not necessarily restricted to use with devices of this kind, but may be employed equally as well with other forms of insulators.

Vieferring now more particularly to the drawings, the stem or insulator body portion of' the spark plug` is indicated at 5, the said stein portion being formed of porcelain or other well known commonly used plastic. Arranged upon the stem portion of the insulator and adjacent the lower end thereof is a body plug 6, the latter being secured upon the stem in any preferred manner, and is by means of threads engaged with the jacket 7 as shown. rlhis jacket is provided with a downwardly extending threadcd portion 8 for engagement with corresponding threads in an engine cylinder, and a .fixed contact S) projects from the lower extremity of the said portion and extends across the lower portion of the insulator stci rlhe reinforcing or strengthening means for insulators of this character comprises a core 10 constructed of any suitable metal and extending centrally throughout the length of the stem portion 5 of' the insulator. The endsv of the core project beyond the opposite extremities of the insulator stem, the lowermost of said projecting ends comprising a contact adapted to cooperate with the fixed contact 9 in producing the spark gap, while the uppermost protruding end of the core is threaded as shown and is equipped with binding nuts 11 by means of which wires or other conductors may be secured to the said plug. In the form of the invention disclosed in Fig. 1 of the drawings, the core 10 is provided with a plurality of outwardly extending arms 12, the latter varying in length throughout the extent of the stem 5. and are provided at their outer extremities with knobs or enlargements 13. When a core of this character is molded within the plastic stern portion 5, it is apparent that the various arms and knobs will constitute anchoring means forsecuring the plastic to the core, and for reinforcing or strengthening the plug stem. The outer shell or body portion 6 may, if desired be baked upon the stem portion 5 of the insulator to more firmly bind the same upon the stem, and to additionally reinforce the latter. lt will be observed that an outwardly projecting flange 141 is formed in the construction of the insulatorI stem 5, the said flange being engaged by the shell or body plug 6, whereby the various re1novable parts are firmly held in assembled position when the plug is to be used.

In Figs. 3 and 11 of the drawings the core 10 is hollow, and is provided with the radially disposed anchoring arms 15, the latter being wedge shaped in cross section so as to facilitate firm seating or anchoring of the reinforcing core to the plastic material of which the stem 5 is formed. In this form of device, a conductor 1G may be arranged within the hollow core.

In Figs. 5 and G there is shown a further modified form of the invention, wherein a hollow core 17 is extended centrally through the porcelain stem of the insulator, and the outwardly projecting arms are disposed with apertures 18 being arranged throughout the extent of the hollow core within which the plastic of the stem 5 engages. l/Vhen the plug is molded around the hollow perforated core, the plastic will enter the various openings and will firmly secure the core to the stem portion of the plug. In this form of device the conductor 16 is used in the same manner as in the form shown in Figs. 3 and t.

From this description it will be observed that a simple and thoroughly eflicient means for reinforcing or strengthening the fragile plastic insulators is provided. By the use of reinforcing means of this character it will be readily apparent that the spark plugs or insulators are rendered practically indestructible, are proof against breakage or chipping, and yet will prove thorrmghly practicable and el'licient.

l'Vhile the above is a description of the preferred embodiments of the invention, it is to be understood that various alterations or changes in the minor details of construe` tion may be resorted to without departing from the spirit of the invention or exceed ing the scope of the claims.

I claim:

1. In an insulator, a hollow metallic core extending throughout the length of the insulator, arms projecting outwardly from said core and embedded in the body portion of said insulator, and a conductor extending through said core, substantially as described.

2. In an insulator, a hollow metallic core extending throughout the length of the insulator, arms projecting outwardly from the said core and embedded in the body portion of said insulator, said arms being of a shape to prevent vertical or lateral movement of said core with relation to said insulater body, and a conductor extending through the core.

3. In an insulator, a hollow metallic core extending throughout the length of the insulator', arms projecting radially from said core, the arms being enlarged at the outer extremities thereof and embedded in the body portion of said insulator, and a conductor extending through said core.

In testimony whereof I aliix my signature in presence of two witnesses.

JOHN SAYER.

Witnesses Jon DENT,

J. H. BROWN.

Copies of this patent may be obtained for five cents each, by addressing the Commissioner of Patents, Washington, I). C. 

